Bag settler for bag filling machines

ABSTRACT

The saddle member of a settler is mounted on a lever fulcrumed on a mounting plate assembly. The other end of the lever is connected to a vertically reciprocating crank rod. The crank rod is driven from a drive shaft by an eccentric cam mounted on the drive shaft and a yoke on the crank rod so that it reciprocates with a harmonic motion. Interposed between the lever end and the crank rod are two springs, one located above the lever and one below. The springs tend to absorb a portion of the reciprocating motion of the crank, the amount of absorption being greater of the bag weight increases. Thus a smaller amount or vibration is transmitted to the bag as it approaches its filled condition thus improving the operation of the scale mechanism of the bag filling machine.

[451 July 31, 1973 [5 4] BAG suntan ron BAG FILLING MACHINES [751investors rfiv'ih'mnau;mm

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[22] Filed: Apr. 16, 1971 [21] Appl. No.; 134,575

[52] US. Cl 141/73, 141/83, 141/114, 141/315, 177/118, 259/D1G. 42 [51]Int. CL... .Q. B651) [/22 [58] Field of Search", 73/242.13 R; 141/68, I141/71, 73-77, 83,114, 315; 177/118; 259/72, DIG. 42

FORElGN PATENTS OR APPLICATIONS 936,255 12/1955 Germany 141/76 PrimaryExaminer-llouston S. Bell, Jr. Attorney-label Baker York and JonesABSTRACTv The saddle member of a settler is mounted on a lever fulcrumedon amounting plate assembly. The other end of the lever is connected toa vertically reciprocating crank rod. The crank rod is driven from adrive shaft by an eccentric cam mounted on the drive shaft and a yoke onthe crank rod so that it reciprocates with a harmonic motion. lnterposedbetween the lever end and the crank rod are two springs, one locatedabove the lever and one below. {1' he springs tend to absorb a portionof the reciprocating motion of the crank, the amount of absorption beinggreater of the bag weight increases. Thus a smaller amount or vibrationis transmitted, to the bag as it approaches its filled condition thusimproving the operation of the scale mechanism of the bag fillingmachine.

Patented Jul '31, 1973 3,749,142

3 SheetsSheet 1 .1 g 3 INVENTOR ERWIN M. L u

WM'YS Patented July 31, 1973 3,749,142

3 Sheets-Sheet 2 Q QQQ INVENTOR ERWIN M. LAU

I Z WW'YS Patented Jul 31, 1973 3,749,142

- 3 Sheets-Sheet 3 IN VE N TOR ERW/N M. LAU

BYW

ATT'YS BAGSETTLER FOR BAG FILLING MACHINES This invention relates to abag settling device for bag filling machines. In such devices, thesettling action is obtained by vibrating a saddle on which the bag restsas it is being filled.

The bag filling machine is one having a spout which is received withinthe valve of a valve type bag, and the bag is partially supported fromthe spout and partially supported by the saddle, both being connected toscale mechanism. When the contents of the bag reaches a predeterminedweight, such as 100 pounds, the scale mechanism trips and terminates thefilling operation.

1 BACKGROUND OF THE INVENTION It has been found that the vibration ofthe bag and bag contents interferes with the uniform terminating actionof the scale mechanism. This is due to the fact that the vibrations aretransmitted to the scale mechanism, partly through the spout, and partlydue to the reaction of the saddle.

As pointed out in my earlier U.S. Pat. No. 3,1 15,905, patented Dec. 31,1963', these vibrations may also be transmitted to the bearing points ofthe scale mechanism causing damage or undue wear.

The problem of interference with theoperation of the weighing mechanismwas recognized in Douglas U.S. Pat. No. 2,981,349, but the solutionproposed,

that of dynamically balancing the drive shaft with counter weights, doesnot constitute an effective solution because it in no way reduces themagnitude of the vibrations transmitted'by the bag to thespout.

Certainaspects of the problem were also recognized inVredenburg, U.S.Pat. No. 2,602,626 in which it was SUMMARY OF THE INVENTION I have foundthat by coupling the driving means to the vibrating system through adouble acting resilient means that the vibration of the bag reduces inmagnitude as the bag approaches the filled condition. The doubleactingresilient means increases the isolation of the saddle from thedrive means as the mass of the oscillating system comprising the saddleand the bag contents is increased when the bag is being filled. In theconstruction shown herein, the vibratory force on the bag at this timecan hardly be detected by the operators hand. Thus, although vibrationsof substantial magnitude are transmitted to the bag contents during theearly stages of the filling cycle, as it approaches the end of thefilling cycle, the vibrations are reduced to an extent where they do notinterfere with the operation of the scale mechanism and furthermore, nodamage or unduewear of the bearingpoints occurs. l have found that theaccuracy of my improved bag filling machine is substantially the same asthat ofa machine in which the settler mechanism is eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: FIG. 1 is a frontelevation of a bag filling machine embodying my invention;

FIG. 2 is an enlarged front view of the settler device;

FIG. 3 is a plan view taken along line 3-3 of FIG. 2;

FIG. 4 is a side elevation of the settling device;

FIG. 5 is a plan section taken along line 5-5 of FIG. 4 with the saddleflanges omitted;

FIG. 6 is a vertical section taken along line 6-6 of FIG. 3;

FIG. 7 is an enlarged detail view of a portion of FIG. 6, with thecollar shown in section; and

FIG. 8 is a section taken along line 8-8 of FIG. 4 showing a detail.

The reference numeral 10 in FIG. 1 indicates a bag filling machine onwhich is mounted a settler 18. The bag filling machine 10 comprises aframework 11 which supports a hopper or chamber 12 for receivingmaterial to be packed into bags. It also includes a spout 13 which ismounted on a floating frame 14. The machine shown is an auger type ofmachine and the construction of the floating frame and the elements ofthe scale mechanism is shown in Lau U.S. Pat. No. 3,301,340 granted Jan.31, 1967. However, the invention is applicable to other types of bagfilling machines. In th particular construction shown, the floatingframe 14 is supported by leaf springs, not shown, from an elementrigidly associated with the framework 1], and suitable flexible conduitmeans, not shown, connect the spout 13 with the interior of the hopper10 so that the spout and the floating frame 14 are free for relativemovement with respect to the framework 11 to actuate suitable scalemechanism 15.

The scale mechanism includes a fulcrum bar 16 fixed with respect to theframework 1 I which engages a scale beam 17. Leaf springs 14a connectthe floating frame 14 to the scale beam 17 so thatwhen the weight of thecontents of a bag supported from the floating frame 14 reaches apredetermined amount, such as 100 pounds, the scale mechanism will betripped to discontinue the filling action.

A pair of hanger rods 19 are screwed to the front face of a plate 20,forming a part of the floating frame 14. The hanger rods include hookportions 21, shown in FIG. 4, which hook over the top of the plate 20.The exact means for connecting the hanger rods to the scale mechanismvaries with different types of scale construction.

The hanger rods 19 each have a series of holes 22 so that the settler 18can be mounted at various elevations, depending upon the length of thebag to be filled, and which is supported from the spout 13.

The settler 18 comprises a mounting plate assembly 23 (FIG. 5) providingtwo pairs of plates, each pair comprising an inner plate 24 and an outerplate 25. The plates are maintained in horizontally spaced relationshipby one or more horizontal pillars 26.

There are two U-shaped brackets 27 mounted on each of the outer plates25, as shown in FIGS. 2, 4 and 5. Each upper bracket has a nut 28 weldedto it and a hand screw 29 extends through the nut and the bracket intoone of the holes 22 of a hanger rod 19.

No screw is required for the lower bracket 27, which merely serves todefine the relative positions of the hanger rod and the mountingplateassembly. Thus, by

removing the two hand screws 29 the vertical position of the settler 18can be adjusted.

The outer plates 25 are each provided with a flange 30 to each of whicha flanged bracket 31 is secured, as shown in FIG. 5. The outer ends ofthe brackets 31 support a vertical plate 32 which serves as a mount fora motor 33. The latter drives a shaft 34 through a belt 35 and suitablepulleys.

A bearing block 36 is mounted on the lower end of the flanges 30, andthe shaft 34 is journaled at either end in the bearing blocks 36, asshown in FIG. 5.

Two eccentric-type earns 37, one being shown in FIG. 6, are mounted onand keyed to the shaft 34. The cams drive the yoke 38 of a reciprocatingdrive member in the form of a crank rod 40 through suitable ball bearingunits 39. The crank rod 40 vibrates the saddle 41 by means hereinafterdescribed.

In the embodiment shown, the machine is provided with two saddle members41, although a single saddle member may be used if desired. Since theseparate drive mechanisms for each saddle member are substantiallyidentical to each other, the same reference numerals are applied to thecorresponding parts of each, and only one is described herein. Eachsaddle member 41 has a side flange 42 and an inner depending flange 43,as shown in FIG. 2. The two inner flanges 43 are spaced from each otherto receive the seam of the bag being filled.

Each saddle member has two depending arms 44 which are pivotallyconnected to a lever 45 which is fulcrumed on a shaft 46 mounted in themounting plate assembly 23. A second shaft 47 provides a pivotalconnection between the depending arms 44 and the outer end of the lever45. Each lever 45 has two hub portions 48, one for the shaft 46 and onefor the shaft 47. For each hub, which is in the form of a hollowcylinder, there are two flanged hard rubber bushings 49, which receivethe respective shaft 46 or 47. The shaft is headed at one end and isthreaded to receive a nut at the other so that the various parts areretained in operating relationship.

A link 50 also connects the depending arms 44 with the plate assembly23, by means of pivoted connections 51 which are the same as the shaft,the hub portions and the flanged bushings above described. Thus the 4lever 45 and the link 50 together with the elements 44 and 23 comprise alinkwork which maintains the arms 44 always in a vertical positionduring oscillation of the saddle member 41, as hereinafter described.

The inner end of the lever 45 terminates in a collar 53 having acentrally inwardly directed flange 54, as shown in FIG. 7. The crank rod40, which is threaded, extends through the collar 53, and upper andlower springs 55 and 56 respectively, surround the rod 40 and areconfined between nuts 57 and the flange 54. The springs 55, 56 togetherwith elements 40, 53 and 57, comprise a double acting spring assembly 60which is preloaded so as to provide a self restoring action on thecollar 53.

In operation, movement of the crank rod 40 upwardly is resisted by thedifference between the forces exerted by the upper and lower springs 55,56, as is movement of the crank rod 40 in the downward direction. At allstatic conditions of bag weight, the collar 53 will seek a position ofequilibrium in which the net force exerted by the springs 55, 56balances the weight of the bag contents, which means that as the bag ap-3 bottom spring 56 if the pinters 59 read equal vvalues due to the netweight of the saddle assembly which includes elements 41, and 50.

In operation, a bag, not shown, is fitted over the spout 13. Then themachine 10 is turned on which causes material to be fed through thespout and into the bag, and at the same time, the saddle members 41 arevibrated. When the bag is almost empty, the vibrating movement of thebag and contents will not cause any appreciable force to be transmittedto the spout l3, and thence to the floating frame 14. This is due to theslackness of the bag. However, as the bag approaches filled condition,the bag walls fill out and would ordinarily transmit vibrations to thespout 13. Additionally, there is a certain reaction of the saddle member41 against the bag, which reaction would tend to be transmitted throughthe mounting plate assembly 23 to the hanger rods 19 and the floatingframe 14.

These forces acting on the floating frame 14, unless reduced by thespring isolation means described herein, will cause a nonuniformoperation of the scale mechanism from one filling operation to the next,because a net downward force applied to the floating frame 14 will causethe scale mechanism to trip prior to the time intended, and a net upwardforce would tend to delay the tripping, this variation in accuracy beingas much as a pound in either direction in the case of a 100 0 pound bag.

However, according to my invention, as the bag approaches its filledcondition, the double acting spring assembly 60 reduces verysubstantially the magnitude of the vibratory force transmitted to thebag. Assuming 5 a pound bag, the net vibratory force on the bag canhardly be detected by the operators hand, and it is estimated that itsforce is only about one-tenth of the vibratory force which istransmitted to the bag contents in the early stage of the fillingoperation. The reaction is corresondingly reduced.

I have found that the accuracy of the scale mechanism according to myinvention, is substantially the same as if the settler mechanism wereeliminated. Nevertheless, the bag contents are effectively settled toprovide the desired density of packing.

The two eccentrics 37, when offset from each other by I80", exert acertain counterbalancing action with respect to each other. However, Iprefer to provide a separate eccentric counterweight 61 for eacheccentric cam 37. Each is keyed to the shaft 34, offset from itsassociated eccentn'c cam 37, according to standard practice. Also, theuse of the counterweights permit the two eccentric cams 37 to beoperated in phase with each other, or at any other desired phaserelationship. The counterweights 60 and eccentrics 37 are spaced fromeach other and from the bearings 36 by means of suitable spacers 62, asshown in FIG. 5.

and engages the plate 32 through nuts 65 so that the belt tension may beadjusted. Also, by removing the nuts 65, the plate 32 and the motor 33may be swung out, after the belt has been removed, giving access to thenuts 57 by means of which the spring tension of the double acting springassembly 60 may be adjusted. As shown in FIG. 8, the T-bolt 64 includesa cross head 65 located between the inner plates 24 and pivotallysecured thereto by screws 66.

In a practical embodiment of my invention, the shaft 34 is driven at1800 RPM. The eccentricity of earns 37 is rs-inch radius, giving aKr-inch amplitude of vibration, the arms of lever 45 being of equallength.

The springs 55 and 56 are Rambler automobile valve springs Part No. VS768 having an overall length of 2% inches. On a compression test, theapplication of 25 pounds pressure reduced the length by /a-inch, thusgiving an elastic spring constant of 200 pounds per inch deflection foreach spring. The weight of each saddle assembly, comprising elements 41,45, 50, is about pounds.

Although only a preferred embodiment of my inven- .tion has been shownand illustrated herein, it will be understood that various modificationsand changes can be made in the construction shown without departing fromthe spirit of my invention, as pointed out in the appended claims.

I claim:

l. A bag filling machine comprising scale mechanism responsive to theweight of the contents of a bag being filled for terminating the fillingcycle of said bag filling machine, a settler for vibrating a bag as itis being filled, and means for suspending said settler from said scalemechanism, said settler comprising a saddle assembly, a reciprocatingdrive member therefor, and means for supporting said saddle assembly onsaid suspending means, said saddle assembly including a saddle memberengaging the bottom of said bag and a member connecting said saddlemember and said drive member, means for imparting harmonic reciprocatingmotion to said drive member, and double acting resilient meansinterposed between said drive member and said connecting member forincreasing the isolation of said saddle assembly from said drive memberas the mass of the oscillating system comprising said saddle assemblyand said bag contents is increased when said bag is being filled.

2. A bag filling machine as claimed in claim 1 in which said connectingmember is a horizontally disposed lever, said harmonic motion impartingmeans comprises an eccentric cam, and said drive member comprises avertically disposed crank rod having a yoke engaging said eccentric cam.

3. A settler for use in a weighing type bag filling machine comprising abody member adapted for connection to the scale mechanism of said bagfilling machine, a lever pivoted in said body member, a saddle memberpivotally connected to one end of said lever, a reciproeating drivemember connected to the second end of said lever, means for impartingharmonic reciprocating motion to said drive member to vibrate saidsaddle member, anddouble acting resilient means interposed between saiddrive member and said second end of said lever for increasing theisolation of said saddle member from said drive member as the load onsaid saddle is increased by the increase in the weight of the contentsof a bag supported by said saddle member.

4. A settler as claimed in claim 3, in which said saddle member includesa depending arm, said lever being pivotally connected to said saddlemember at said depending arm, and a link member spaced from said leverand disposed parallel thereto and extending between said body member andsaid depending arm and forming with said lever, depending arm, and bodymember, a linkage whereby said saddle is maintained in an uprightposition.

5. A settler as claimed in claim 3 in which said harmonic motionimparting means includes a drive shaft,

an eccentric cam on said drive shaft, said reciprocating drive memberincluding a yoke surrounding said eccentric cam, and a motor for drivingsaid drive shaft.

6. A settler as claimed in claim 5 which includes a motor mounting platepivotally mounted at its upper end on said body member, releasable meansfor securing the lower end of said motor mounting plate to said bodymember whereby said motor mounting plate can be swung upwardly and awayfrom said reciprocating drive member to provide access to said resilientmeans.

7. A settler as claimed in claim 3 which includes a collar mounted onsaid second end of said lever, said reciprocating drive member extendingthrough said collar, two adjusting nuts threaded on to said drivemember, one being above said collar and one being below said collar,said double acting resilient means comprising a pair of coil springs,one being confined between said collar and said upper nut, and the otherbeing confined between said collar and said lower nut whereby saidsprings resist relative axial motion between said collar and said drivemember in both axial directions.

8. A settler for use in'a weighing type bag filling machine comprising amounting plate assembly adapted for connection to the scale mechanism ofsaid bag filling machine, two horizontally disposed levers pivoted sideby side in said mounting plate assembly, two saddle members each beingpivotally connected to the outer end of one of said levers, twovertically reciprocating drive members each being connected to the innerend of one of said levers, eccentric means for imparting harmonicreciprocating motion to each drive member to vibrate said saddle membersin opposed phase relationship, and double acting resilient meansinterposed between each drive member and its associated lever forincreasing the isolation of each saddle member from its associated drivemember as the mass of the oscillating system comprising said two saddlemembers and the contents of a bag supported thereby is increased whensaid bag is being filled.

$ t i t

1. A bag filling machine comprising scale mechanism responsive to theweight of the contents of a bag being filled for terminating the fillingcycle of said bag filling machine, a settler for vibrating a bag as itis being filled, and means for suspending said settler from said scalemechanism, said settler comprising a saddle assembly, a reciprocatingdrive member therefor, and means for supporting said saddle assembly onsaid suspending means, said saddle assembly including a saddle memberengaging the bottom of said bag and a member connecting said saddlemember and said drive member, means for imparting harmonic reciprocatingmotion to said drive member, and double acting resilient meansinterposed between said drive member and said connecting member forincreasing the isolation of said saddle assembly from said drive memberas the mass of the oscillating system comprising said saddle assemblyand said bag contents is increased when said bag is being filled.
 2. Abag filling machine as claimed in claim 1 in which said connectingmember is a horizontally disposed lever, said harmonic motion impartingmeans comprises an eccentric cam, and said drive member comprises avertically disposed crank rod having a yoke engaging said eccentric cam.3. A settler for use in a weighing type bag filling machine comprising abody member adapted for connection to the scale mechanism of said bagfilling machine, a lever pivoted in said body member, a saddle memberpivotally connected to one end of said lever, a reciprocating drivemember connected to the second end of said lever, means for impartingharmonic reciprocating motion to said drive member to vibrate saidsaddle member, and double acting resilient means interposed between saiddrive member and said second end of said lever for increasing theisolation of said saddle member from said drive member as the load onsaid saddle is increased by the increase in the weight of the contentsof a bag supported by said saddle member.
 4. A settler as claimed inclaim 3, in which said saddle member includes a depending arm, saidlever being pivotally connected to said saddle member at said dependingarm, and a link member spaced from said lever and disposed parallelthereto and extending between said body member and said depending armand forming with said lever, depending arm, and body member, a linkagewhereby said saddle is maintained in an upright position.
 5. A settleras claimed in claim 3 in which said harmonic motion imparting meansincludes a drive shaft, an eccentric cam on said drive shaft, saidreciprocating drive member including a yoke surrounding said eccentriccam, and a motor for driving said drive shaft.
 6. A settler as claimedin claim 5 which includes a motor mounting plate pivotally mounted atits upper end on said body member, releasable means for securing thelower end of said motor mounting plate to said body member whereby saidmotor mounting plate can be swung upwardly and away from saidreciprocating drive member to provide access to said resilient means. 7.A settler as claimed in claim 3 which includes a collar mounted on saidsecond end of said lever, said reciprocating drive member extendingthrough said collar, two adjusting nuts threaded on to said drivemember, one being above said collar and one being below said collar,said double acting resilient means comprising a pair of coil springs,one being confined between said collar And said upper nut, and the otherbeing confined between said collar and said lower nut whereby saidsprings resist relative axial motion between said collar and said drivemember in both axial directions.
 8. A settler for use in a weighing typebag filling machine comprising a mounting plate assembly adapted forconnection to the scale mechanism of said bag filling machine, twohorizontally disposed levers pivoted side by side in said mounting plateassembly, two saddle members each being pivotally connected to the outerend of one of said levers, two vertically reciprocating drive memberseach being connected to the inner end of one of said levers, eccentricmeans for imparting harmonic reciprocating motion to each drive memberto vibrate said saddle members in opposed phase relationship, and doubleacting resilient means interposed between each drive member and itsassociated lever for increasing the isolation of each saddle member fromits associated drive member as the mass of the oscillating systemcomprising said two saddle members and the contents of a bag supportedthereby is increased when said bag is being filled.